HV insulation

ChinSun oil to air feedthroughs are capacitive feedthroughs with RIS/RIP insulating core technology. The design, components and bushing technology ensure an average lifespan of more than 30 years under normal operating conditions.

ChinSun oil-air bushings are designed for heavy cantilever loads. They comply with the IEC 60137-2017 standard for insulated bushings for AC voltages up to 750 kV. They are designed for use in power transformers and can be installed with a maximum inclination of 45° from vertical (up to and including 420 kV) or 30° (550 kV and above).

RIS technology

Resin Impregnated Plastics (RIS) are the latest technology in the high voltage bushing industry (at ChinSun we have more than 10 years of production experience). More and more energy projects require paperless implementations to ensure excellent performance from their transformers. Yes, this is the current trend in the high voltage bushing market, which is in many ways consistent with RIP (Resin Impregnated Paper) technology. But although RIS has many similar characteristics to RIP technology, RIS stands out in the following aspects:

• The RIS grommet does not contain any hygroscopic material such as waste paper and is therefore easier to store.
• Partial discharge for double voltage between phase and earth.
• Completely dry grommet, no oil leakage, no risk of explosion
• Shipping time is shorter than RIP grommets because resin impregnation time is reduced
• No maintenance required
• ChinSun® RIS grommet technology is one of ChinSun’s national patents. Thus, ChinSun, as the original inventor of this type of RIS grommet, is a strong competitor in terms of technology and price.

Introducing filling paste into porcelain bushings

ChinSun uses a special filling paste between the inner and outer insulation gap of the bushing.

It is characterized by resistance to changing weather conditions, cold, moisture, acids, alkalis, exemplary tightness, volume resistance, high insulation breakdown voltage, very good dielectric loss factor, low expansion coefficient and high thermal stability. The insulating polymer does not contain metal ions or other harmful substances.

It is a special material for filling the gap of a high voltage line, which has good compatibility with the inner capacitive core and the outer porcelain casing. When filled with paste, the bushing is well protected against moisture, water and expansion or contraction of the insulation. So we can solve leakage problems and protect the grommet under various environmental and climate conditions to ensure stable and reliable operation.

This guarantees the safe use of the cuff in various environments, including harsh weather conditions.

To what standard is the ChinSun® pipe manufactured and tested?

The ChinSun® protective conduit not only meets all specifications required by IEC 60137, but also the electrical, thermal and mechanical properties of the relevant IEEE standards. The ChinSun grommets have a very low dielectric loss coefficient tanδ of typically < 0.35%, while the electrical design of the grommets and the gapless impregnation process have guaranteed their resistance to incomplete discharges up to twice the maximum phase-to-earth operating voltage, defined on a background noise of 2 pC of the incomplete discharge measurement. This data is significantly better than the values specified in the IEC standard for RIP bushings, i.e. H. dielectric loss <0.7%, incomplete discharge <10 pC and <5 pC at 1.5 and 1.05 times the maximum phase-to-ground operating voltage, respectively.